Clinical orthotopic liver transplantation is being carried out on approximately 20 patients per year using improvements in surgical, diagnostic and management techniques that have recently evolved. Thoracic duct fistula as immunosuppressive adjuvant will be added. Patients with inborn errors of metabolism will have biochemical studies dictated by the nature of the enzyme defect and metabolic abnormalities. Supporting laboratory investigations are directed to the evaluation of new agents, including cyclosporin A, development of better methods of liver preservation, definition of the best timing for thoracic duct fistula, and evaluation of auxiliary liver transplantation for the treatment of acute hepatic failure.